Cubase AI LE9 not recognising UR12 as audio device

I have purchased the UR12 interface and successfully installed it on a Mac OS Sierra 10.12.6. I have checked ‘Applications’ - ‘Utilities’ - ‘Audio MIDI setup’ to confirm the existence of the UR12 as an audio device. I have successfully downloaded the enclosed Cubase software (‘Cubase AI LE Elements 9’), which opens without issue. However, with ‘Audio MIDI setup’ open, when I open Cubase the UR12 disappears from the list of audio devices and Cubase tells me that Cubase AI LE Elements 9 has detected new auto drivers and offers the choice of internal audio or the UR12. Selecting the UR12, it then tells me ‘The audio driver could not be loaded. Please ensure your audio hardware is connected properly to your computer’. Is this because I unplugged the UR12 and plugged it into a powered USB hub (mbeat 7-port powered hub, with the UR12 definitely receiving power)? Do I simply need to repeat the device installation?